Feame foe stretching canvas



UNITED STATES PATEN T OFFICE.

HENRY BRYANT, OF HARTFORD, CONNECTICUT.

FRAME FOR STRETCI-IING CANVAS.

Specification of Letters Patent No.

To all whom it may concern Be it known that I, HENRY' BRYANT, of thecity of I-Iartford, in the county of Hartford and State of Connecticut,have invented a new and useful improvement in the construction of framesfor stretching canvas and other materials, for portrait and landscapepaintings, and for other purposes; and I do hereby declare that thefollowing is a full, clear, and exact description of the constructionand operation of the same, reference being had to the accompanyingdrawings, which make a part of this specification, in which- Figure 1 isa perspective view of the frame, with the canvas stretched thereon,showing the metallic plates in the corners of the frame, and the methodof securing them by means of binding screws; and the wedges, or keys, bywhich the canvas is to be stretched. Fig. 2, is a perspective view ofone of the metallic plates, showing the slots through which the bindingscrews pass, to firmly secure the covers of the frame. Fig. 3, is aperspective view of the mitered ends of two of the parts of the frame.Fig. 4, is a perspective view of one of the wedges, or keys used instretching the canvas. Fig. 5, is a perspective view of one of thebinding screws which secure the metallic plates.

My improvement consists in making the frame without mortise or tenon, bysimply cutting the ends of the four parts of the frame to a miter, andbringing the parts together so as to form right angles at each corner,and securing them in that position by metallic plates held in theirproper positions by binding screws inserted through slots in each of thelimbs of the plates. These plates, when thus secured, will hold thecorners of the frame entirely firm, while the binding screws, beingmovable in the slots, will allow the four parts of the frame to beforced outward by means of four wedges, or keys driven into the jointsat the four corners of the frame; by which means the canvas will beequally stretched, as that part which is least stretched, while nailingit onto the frame, will yield most readily to the force of the wedges,or keys; by all which means the corners of the frame will be always keptat right angles, and the frame prevented from springing or becomingwinding.

I make the four parts A, B, C, and D, of the frame of boards in theusual form, but

6,731, dated September 25, 1849.

instead of joining the corners by mortises and tenons, I cut each of theends to a miter, (as seen in Fig. 3,) and butt them together, as seen atE, F, Gr, and H, Fig. 1. I make the metallic plates of cast iron, orother suitable material, in the form shown in Fig. 2, with two, or moreslots in each of the limbs, as seen at I, K, and L, M, Figs. 2, and 1.These slots must be made in such a position in the two limbs, that aline drawn longitudinally through the center of the slots I, and K, willintersect a line drawn longitudinally through the center of the slots L,and M, at right angles; so that to whatever extent the joints of theframe may be forced open by the wedges, or keys, each of the corners ofthe frame must be a right angle. The plates must be attached to theposterior side of the corners of the frame, by means of binding screws,as represented at E, F, G, and H Fig. 1, the screws being at the end ofthe slots nearest to the angle, to allow the part of the frame to spreadto any extent ren quired.

The joints, at the corners of the frame, are to be forced open, to thenecessary extent for stretching the canvas to the required tension, byjam wedges or keys, as shown at N, O, P, and Q., Fig. 1, driven in thedirection of the miter, thereby operating both ways, that is, tolengthen and widen the frame at the same-time.

The effect of the driving of the wedges, or keys, (while the corners areheld in their right angular positions by the plates, as beforedescribed,) will be to stretch the canvas with the utmost uniformitythroughout every part, as the parts of the frame will yield most readilyto the force of the wed ges, or keys, in the direction of the leaststrain.

When the canvas has been thoroughly stretched, by the wedges, or keys,small tacks, or points, may be driven into the frame at the end of eachlimb of the metallic plates, as seen at a, c, and d, Fig. l, so that thewedges, or keys will not be needed, as the frame will be held firmly tothe great est degree of tension even if the wedges, or keys, should dropout.

The advantages of my improvement consist in so making the frame, that,by means of the mitered corners secured by the metallic plates, thejoints may always be held sufliciently rm, and the corners alwayspreserved at right angles, and the whole frame kept from springing, orbecoming winding,

under all circumstances, While the slots in the metallic plates willallow the binding screws sufficient space for all the stretching thatWill ever be necessary. And but four Wedges, or keys, will be neededWhere eight is new used.

Vhat I claim as my invention, and desire to secure by Letters Patent, is

The method of constructing the .frame 10 Without mortise or tenon, bycutting the corners to a ymiter and securing them by metal-

